I posted a series to change this behavior: https://mail.openvswitch.org/pipermail/ovs-dev/2019-November/364812.html https://mail.openvswitch.org/pipermail/ovs-dev/2019-November/364811.html
On Wed, Nov 06, 2019 at 10:13:16AM -0800, Ben Pfaff wrote: > You might be right. > > I don't think this affects what actions we shoudl take, though. It > still seems better to use "exit" to stop OVS gracefully. > > I'm working on a patch to make "exit" avoid removing flows unless > --cleanup is passed in. It's slow going because I've got higher > priorities things to do. > > On Wed, Nov 06, 2019 at 09:39:12AM -0800, Guru Shetty wrote: > > It may have come from this commit instead: > > > > commit 9b5422a98f817b9f2a1f8224cab7e1a8d0bbba1f > > Author: Ilya Maximets <[email protected]> > > Date: Wed Dec 16 15:32:21 2015 +0300 > > > > ovs-lib: Try to call exit before killing. > > > > While killing OVS may not free all allocated resources. > > > > Previously we used to SIGTERM ovs-vswitchd and even now, it looks like > > doing that prevents the flush of datapath flows. > > > > On Fri, 1 Nov 2019 at 13:35, Ben Pfaff <[email protected]> wrote: > > > > > OVS currently can gracefully exit in two ways: either with or without > > > deleting the datapath. But, either way, it deletes all of the flows > > > from the datapath before it exits. That is due to commit e96a5c24e853 > > > ("upcall: Remove datapath flows when setting n-threads."), which was > > > first released in OVS 2.1 back in 2014. > > > > > > This isn't usually a big deal. However, some controller folks I'm > > > talking to are concerned about upgrade. If the datapath flows persisted > > > after OVS exits, then existing network connections (and perhaps some > > > that are "similar" to them because they match the same megaflows) could > > > carry on while the upgrade was in progress. > > > > > > I am surprised that I have not heard complaints about this in the 5 > > > years that the behavior has been this way. Does anyone have any stories > > > to report about it now that I bring it up? Contrariwise, if we changed > > > OVS so that it did not delete datapath flows on exit, can anyone suggest > > > what problems that might cause? > > > > > > Thanks, > > > > > > Ben. > > > _______________________________________________ > > > discuss mailing list > > > [email protected] > > > https://mail.openvswitch.org/mailman/listinfo/ovs-discuss > > > _______________________________________________ discuss mailing list [email protected] https://mail.openvswitch.org/mailman/listinfo/ovs-discuss
